title: Intraportal endovascular ultrasonography for assessment of vascular invasion by biliary tract cancer.
abstract: BACKGROUND
  This study was performed to investigate the diagnostic accuracy of intraportal endovascular ultrasonography (IPEUS) in assessing vascular invasion by biliary tract cancer.
  
  
  METHODS
  A prospective study of 31 consecutive patients with biliary tract cancer was performed. All patients underwent surgery. The sonographic criterion for right hepatic artery invasion was interruption of the hyperechoic layer or encasement by tumor. The sonographic criterion for portal vein invasion was obliteration of the echogenic band of the portal vein. IPEUS findings were confirmed by surgical exploration and pathologic examination of resected specimens.
  
  
  RESULTS
  Right hepatic artery invasion was confirmed in resected specimens in seven patients and by operative findings in four patients. Portal vein invasion was confirmed in resected specimens in six patients and by operative findings in five patients. For diagnosis of right hepatic artery invasion, the sensitivity, specificity, and overall accuracy of IPEUS were all 100%; respective values were 63.6%, 84.2%, and 76.7% for angiography. For diagnosis of portal vein invasion, the sensitivity, specificity, and overall accuracy of IPEUS were 100%, 95%, and 96.8%, respectively. The corresponding values were 63.6%, 89.5%, and 80% for portography and 54.5%, 85%, and 74.2%, respectively, for CT.
  
  
  CONCLUSIONS
  IPEUS will improve the assessment of vascular invasion at the hepatic hilum by biliary tract cancer.
authors.affiliation: Department of Surgery II and Radiology, Faculty of Medicine, University of Nagoya, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kaneko
authors.forename: A
authors.initials: A
authors.lastname: Nakao
authors.forename: S
authors.initials: S
authors.lastname: Nomoto
authors.forename: T
authors.initials: T
authors.lastname: Endo
authors.forename: S
authors.initials: S
authors.lastname: Ito
authors.forename: H
authors.initials: H
authors.lastname: Takagi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001661:Biliary Tract Neoplasms / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000473:pathology; D019160:Endosonography / Q000379:methods*; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D006503:Hepatic Veins / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D011169:Portal Vein / Q000000981:diagnostic imaging / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional / Q000379:methods*